Cooling and heating system utilizing solar heat

Abstract

A cooling and heating system utilizing solar heat comprises a heat collector for heating a circulating heat medium with solar heat, an absorption refrigerator operable with the heat medium heated by the heat collector and serving as a generating heat source to provide a chilled medium, and an air-conditioning unit for circulating the chilled medium or the heated medium alternatively therethrough to cool or heat the space to be air-conditioned. The system further comprises a bypass line provided with an auxiliary refrigerator of the dual-effect type and connected to an intermediate portion of a line extending from the absorption refrigerator to the air-conditioning unit for supplying chilled medium or the heated medium to the unit. Change-over means is provided for passing the chilled medium or the heated medium through the bypass line.

We claim: 
     
       1. In a cooling and heating system utilizing solar heat comprising: a solar heat collector (1),   a heat accumulator (2) for storing fluid heated by solar heat obtained by said solar heat collector (1),   a single-effect absorption type refrigerator (4) connected to said heat accumulator (2) via heated fluid circulating lines (3), and actuated by said heated fluid supplied from said heat accumulator (2) to produce chilled fluid,   at least one air-conditioning unit (6) connected to said single-effect absorption type refrigerator (4) via air-conditioning fluid circulating lines (7), and adapted to cool or heat space (S) to be air-conditioned,   heated fluid bypass lines (8) provided between said heated fluid circulating lines (3) and said air-conditioning fluid circulating lines (7) to bypass said single-effect absorption type refrigerator (4), and   change-over valves (V 1 ) provided at junctions (a 1 ), (a 2 ), (a 3 ), (a 4 ) of said heated fluid bypass lines (8) to said heated fluid circulating lines (7), and adapted to selectively changeover between a heating state to supply said heated fluid from said heat accumulator (2) directly to said air-conditioning unit (6) and a cooling state to supply said heated fluid from said heat accumulator (2) to said single-effect absorption type refrigerator (4) and supply the chilled fluid generated by the single-effect absorption type refrigerator (4) to said air-conditioning unit (6),   the improvement comprising:   a further bypass line (11) connected in parallel to an intermediate portion of a forward passage of said air-conditioning fluid circulating lines (7),   change-over valves (V 2 ) provided at junctions (a 5 ), (a 6 ) of said further bypass line (11) to said forward passage of said air-conditioning fluid circulating lines (7) and adapted to selectively changeover between a state to bypass and a state not to bypass said heated or chilled fluid from said forward passage of said air-conditioning fluid (7) to said further bypass line (11), and   an auxiliary gas-burning double-effect absorption type refrigerator (10) provided on an intermediate portion of said further bypass line (11) to further heat or chill the heated or chilled fluid supplied from said forward passage of said air-conditioning circulating lines (7).   
     
     
       2. A cooling and heating system as claimed in claim 1, wherein a header (9) is provided between the bypass line (11) and a return passage portion of the supplying line (7). 
     
     
       3. A cooling and heating system as claimed in claim 1, wherein the change-over means (13) is automatically operable for change-over in accordance with the temperature detected by a temperature sensor (12) disposed upstream from the change-over means (13). 
     
     
       4. A cooling and heating system as claimed in claim 3, wherein the air-conditioning unit (6) is a fan coil unit. 
     
     
       5. A cooling and heating system as claimed in claim 2, further comprising a first branch line (17) extending from the supplying line (7) and adapted to be placed into or out of use by change-over, a second branch line (18) extending from the bypass line (11) and adapted to be placed into or out of use by change-over, and a further air-conditioning unit (19) having the two branch lines arranged in parallel therein for another space (S') to be air-conditioned. 
     
     
       6. A cooling and heating system as claimed in claim 5, wherein the further air-conditioning unit (19) is of the duct type.